Metallurgical furnace



Feb. 2, 1929.

D. CUSHING METALLURGICAL FURNACE Filed July 19, 1926 2 Sheets-Sheet 1 Jawze! (ear/zany:

D. CUSHING METALLURGICAL FURNACE Feb. 26, 1929. 1,703,337

Filed July 19, 1926 2 Sheets- Sheet v2 Patented F 26, 1929.

PATENT OFFICE.

UNITED-STATES nmmx. comma, or LOWELL, mssacnusmrs.

METALLURGICAL manner Application filed m 1a, 1926. Serial No. 123,279.

' This invention relates to'a. furnace for metallurgical operations, particularly adapted to the reduction of non-ferrous metals such as copper, brass, bronze, zinc or tin.

I It is the object of'my' invention to improve such a furnace in several important respects, by which improvements the furnace is beta ter adapted to its intended purposes and by which more satisfactory results are attained. In the operation of such a furnace with non-ferrous metals in the form of chi s or light scra I preferably use a pitch co e or a coke of i'gh compresslve strength and sub stantially free from impurities.

to provide a furnace for such purposes in which the bottom of the cupola or. body.por-

use of forced or natural draft or any combination thereof, but this feature is not claimed herein as it forms the subset matter of a divisional application Serial No. 325,557, filed by me December 12, 1928.

My invention further relates to arrangements and combinations of parts which will be hereinafter described and more particu-- larly pointed out in the appended claims.

A preferred form of the invention is shown in'the drawings in which Fig.1 is a side elevation of a metallurgical "l furnace embodying my improvements;

Fig. 2 is a plan view thereof; Fig. 3 is a partial sectional elevation, taken substantially along the line 33 in Fig. 2;

Fig. 4 is a plan view of the bottom member; and

Fig. 5 is a detail sectional view of a ortion of one of the draft regulating devices.

Referring to the drawings, I have indi-' cated a metallurgical furnace comprising a cupola or body portion 10 and a stack 11 con nected thereto. The cupola has the usual fire brick lining and is provided with a charging door 12, aclean-out door 13, a breast block 14 and a tap spout or runner portion 15, all of substantially the usual construction. The

A more specific object of my invention is breast member 14 is preferably made as a single unit formed of fire brick or other similar refractory material and the openin therein is closed by clay or other material w en the metal is not flowing. The cupola 10 is supported upon an annular frame member 10, mounted on legs 17. The cupola is provided with a lurality of spaced tuyere blocks 20, (Fig. 3 each having a tuyere opening 21 formed therein. Each block 20 preferably consists of a single piece of refractory material with a tuyere opening formed .directly 3 in said material. These blocks 20 form part of the subject matter of my divisional application above noted.

- An outwardly projecting cylindrical member 23 is provided for each tuyere block 20 and forms a portion of the tuyere structure. A fan F or other source of an under pressure 1s connected by. ipes 24, 25 and 26 to.

the cylindrical mem er 23 previously described, and the tlgiyere blocks are thus supplied with air un er'any desired pressure, depending upon the size and speed of the fan F.

The'outer ends of the cylindrical projections 23 are provided with a series of spaced air openings 30 (Fig. 5) which are covered by a cylindrical cap-or sleeve 31 having a series of similar air openings 32. The open ings 32 are spaced apart so that the imperforate portions of the cap between the openings are of suflicient width to close the openings 30 when aligned therewith.

The end portions 33 of the caps 31 are preferabl provided with central 0 enings 34 through which the interior of the. mace may be inspected and each opening34 is preferably closed by a glass or. mica disc 35. Each ca 31 may also be provided with a slot 36 and inding screw 37 by which said cap may be held in desired angular adjustment.

I attain very important advantages by the combination of forced and natural draft which I have shown and above described. With this combination, I may close the openings 30 and operate on the forced draft entirely or I may uncover the o enings 30 partially, thus modifying an reducing the forced air pressure to any desired extent. I may also shut off the fan F and operate entirely under natural draft, regulating the natural draft by the angularpositions of the caps 31. This double control of the air supply has been found extremely usefulin carrying out metallurgical operations upon non-ferrous metals, where it is extremely essential that excessive draft be avoided. 1

Another important feature of my invention relatesto the improved means which I have provided for closing the lower end of v the on ola orbody portion 10. For this purthe annular base mem er and forms a sealing member therefor.

A cross bar 48 extends between the arms 49 on which the bottom member is pivoted, and

" the member 40 may be swung upward to operative position by placing a lever 50 under the member 40 and over the cross bar 48.

When the bottom member 40 has been moved to raised position, a post or brace 51 maybe inserted to hold the member 40 in such raised or operative position. A chain 52 may be provlded" to limit the swinging downward movement of the bottom member.

' When in operation, the bottom member 40 su ports a lining preferably formed of fire brlck 54 fitted within the circular flange 45 and having grooves 55 in their-edge portions adapted to fitover the rib 47. A layer of heat insulating'material 56' is preferably provided between the bottom member 40 and the bricks 54.- The lining is thus retainedfirmly in operative position by the rib 4'7 'and may be additionally secured within'the flange 45 by suitable cement if desired.

The bricks are so firmly secured in position that the bottom member 40 may be swung to operative or inoperative positions without disturbing the lining of the bottom member 40.

After the bottom member has been raised to the position shown in Fig. 3, the opening around and above the flange member 45 may be closed by a suitable sealing material 57, such as fire clay or cement. this sealing material being easily displaced as the bottom member swings downward. The upper face of the fire brick 54 and of the sealing material 57 preferably forms an inclined surface substantial-1y at the level of the tap opening 58,. so that the molten metal in the bottom of the furnace may flow freely to the tap spout l5.

In actual operation, I have found that a bottom member constructed as above described, and particularly when. with the insulating material 56, the re brick lining 54 and the sealing material 57, is exrovided 7 tremely well adapted for use in a furnace delabor is saved by the provision of my remov able bottom member, as the furnace may be opened and cleaned at an time desired'witlb' out disturbing the fire brick liningof the bottom, and it'is only necessary to replace the sealing material 57 to place the furnace again in condition for operation.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed otherwise than as set forth in the claims, but what I claim is 1. A metallurgical furnace comprising a cupola portion, and a removable bottom member having a fire resisting lining permanently secured thereto and movable to and from operative position as a unit therewith, said bottom member and said fire resisting lining having portions formin locking engagement to positively retain said lining in position and the upper surface of said lining being in direct contact with the metal in the furnace and being inclined downward toward the tap spout of the furnace and having its lowest edge portion adjacent and substantially on the level-with said spout.

2. A metallurgical furnace comprising a cupola portion, and a removable bottom mem.-

ber having a fire resisting lining permanently secured thereto and movable to and from operative position as a unit therewith, said bot-. tom member having an upwardly extending flange portion with an internal rib thereon and said lining being formed of fire brick fitting within said flange and grooved to receivesaid internal rib and retained in position thereby.

3.. A metallurgical furnace comprising a cupola portion and a removable bottom member having a fire resisting lining permanent-1y secured thereto and movable to and from operative position as a unit therewith, said bottom member having an upwardly extendin flange rtion and said lining being forme of fire rick secured within said flange portion, and said bottom member having a layer of heat insulating material interposed between said member and said fire brick;

4. A metallurgical furnace comprisinga flange portion and said lining being formed of fire brick secured within said flange portion, said furnace having also w'portion of sealing material disposed aroundand over sealing rim surrounding said flat portion and at an oblique angle thereto and engagin said horizontal bottom face, said annular ange projectin upwardly from said flat body portion and eing adapted tobe received within the lower part of the cylindrical cupola when the bottom member is in operative position.

In testimony whereof I have hereunto affixed 'my signature.

DANIEL CUSHING. 

